A192546 a(n) = sum(stirling2(n,k)*stirling2(n+1,k+1),k=0..n).

1, 1, 4, 26, 251, 3157, 50310, 978315, 22616102, 610543614, 18953178234, 668200802513, 26484030901784, 1169889631517219, 57168091338306720, 3070545537985858612, 180251920018830890897, 11507450028966272232867, 795397552661209049095698

Offset: 0

Author

Emanuele Munarini, Jul 04 2011

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..52

Crossrefs

Cf. A047793

Programs

Mathematica

Table[Sum[StirlingS2[n,k]StirlingS2[n+1,k+1],{k,0,n}],{n,0,100}]
Total/@Table[StirlingS2[n,k]StirlingS2[n+1,k+1],{n,0,20},{k,0,n}] (* Harvey P. Dale, Dec 15 2023 *)

Maxima

makelist(sum(stirling2(n,k)*stirling2(n+1,k+1),k,0,n),n,0,24);